Types of Inference in TTRPGs

[sam_the_bold]

1. For those with a background in game studies, has this been written about or discussed before? Are there other theoretical distinctions this can be mapped onto?
   
2. Why do people seem to prefer one type of inference over another?
   
3. Per the examples above, it seems like inference happens at a lot of different levels -- is it reasonable to conflate the inference done by a referee when prepping a scenario with the inference done by players when running it?
   
4. Are there counterexamples where OSR games rely on deduction, or where storygames rely on abduction?
   

In order:

1. I can't think of any obvious connections? I would be willing to bet there is discussion of inference in the literature surrounding adventure games—that is, point-and-clicks of the flavor made by Sierra On-Line or LucasArts—but I have not read nearly enough to say for sure. I did some very fast searches on gamestudies.org, Analog Game Studies, and the IJRP for these kinds of inferences and found not very much. (A little bit of chatter around ludology-vs-narratology and how each derives meaning, and some stuff in Analog Game Studies about social deduction.) But this specific kind of detail-as-worldbuilding I did not see anything with immediate resemblence. 
   
2. Big question. My sense, in general, is that deduction favors styles of tables and play where discovery is de-prioritized—that is, where there is not some overarching extant truth(s) that need to be understood to progress. Like a lot of adventure-centric playstyles hover around some sort of general loop of transforming uncertainty/lack-of-knowledge into understanding and mastery. You map the dungeon, observe and understand monster weaknesses, learn the secret lore that lets you hit the boss's weakspot. Most of these, to my read, involve one of either abduction or induction, and correspondingly start you as players from a place of relative weakness and uncertainty. On the other hand, in styles of play that revolve less around cooperative problem-solving and more on creating drama and narrative together, it's important that everybody has a relatively strong shared sense of the world, even when the smaller details vary. Like if we're playing a game of Monsterhearts or Stewpot (in the way generally described by their authors), it's important that everybody understands the basic reality of play, because that's what allows each of our characters to make big spicy dramatic plays, the stuff that kicks up the drama. Similarly, as you say, filling in the precise details—say, the contents of my teenage monster's bedroom—is often very fun and expressive for players, and so these sorts of rulesets tend to allow for a lot of variety. We might call those details "fluff" or "flavor." Abduction and induction are really important for playstyles that hinge on discovery and transforming uncertainty into mastery, but for styles that expect players to create their own drama, deduction from general understandings allows a lot of expressive detail-making play—and the specific of those details are unnecessary anyways, since it's not players are ever really uninformed. 
   
3. I don't... think... so? Seems like no, to me, at least most of the time? Inference done as part of prep is largely to supply concrete details, no? Like it's to flesh out the world, to add diegetic detail and material for play. And that is, one way or another, nearly always about making concrete details—like it's basically always deduction or induction, in this sense, even if it follows some abduction. I suppose in a more player-authorial context, one could imagine a similar beat, where players collaboratively flesh out the world based on existing details, sort of like the Unscene in The Between or the leading questions in Stonetop? Kinda? But that's unusual. The other unusual overlap I can think of is in the context of a very tightly-written but very mysterious adventure—like the Wolves hyperwar, or some of the secrets in A Perfect Wife—where there are conclusions the GM needs to abduce out of the text as they read, similar to how the players will abduce those conclusions as they play. "Book : GM :: GM : Players" at its most literal level, sorta. 
   
4. I think deduction is relatively common for GMs in OSRish games when it comes to supply specific details. Like if the book or your prep says that the room has high ceilings but doesn't specify an exact measurement and a player asks "Can my 50' rope reach the chandelier?", your answer as to Yes or No depends on a degree of deduction, extrapolating "high" into a specific number. I think the difference is that many more Trve Simvlationists (like yovrs trvly) view that kind of deduction as something negative, something to be avoided, whereas for many GMs and players it's just business as usual. NPC reactions are another very common and harder-to-solve one: I know an NPC is grumpy and prone to insults, so I can deduce that when a PC asks for help, that NPC is likely to call them names rather than helping, even when that's not specified in the text. For the reverse, abduction in trad/storygames/neotrad, I think it's actually very common, it's just called "implied worldbuilding" or "anti-canon." Like when I spin up a new character and one of my starting gear options is, like, "Badge of the Planetary Constabulary," that, as the classic line goes, suggests something new and compelling about the world. Now the Planetary Constabulary is something more material, something we can hang our game around, potentially, which it (presumably) wasn't before. This is common-ish in more OSR and related projects, too—the key difference, I think, is that in more OSR-leaning stuff all those little details in chargen usually (ideally?) point to things that already exist, whereas in storygamier projects they tend to exist as jumping-off points for the table to create its own lore. Sort of abduction-as-mystery-solving vs. abduction-as-worldbuilding-prompt, if that makes sense.